A new isoflavone isolated from Brachypterum eriocarpum (F.C.How) Adema and Sirich. and its hypolipidemic activity

A new isoflavone, brachypterum-isoflavone A (1), eight known isoflavonoids (2–9), and six known coumarins (10–15) were isolated from the stems of Brachypterum eriocarpum (F.C.How) Adema and Sirich. Compounds 7, 11, 12 and 15 were first reported from this plant. Structures were determined by HR-ESI-MS, NMR, and ECD spectroscopy. Compound 1 showed negligible cytotoxicity (cell viability >92% at 50 μmol/L). At 25 μmol/L, TC and TG levels in the compound 1 group were 0.113 and 0.333 mmol/L, respectively, comparable to those of the lovastatin group (0.094 and 0.296 mmol/L). Oil Red O staining confirmed dose-dependent alleviation of lipid droplet accumulation. Network pharmacology predicted HMGCR as a core target, which was subsequently validated by ELISA. Compound 1 dose-dependently reduced HMGCR protein levels, suggesting that the lipid-lowering activity in FFA-treated HepG2 cells is associated with HMGCR inhibition in the mevalonate pathway, though further in vivo studies are needed to validate the underlying mechanism.